Balanced slide-valve



B. HALE.

BALANCED SLIDE VALVE.

No. 347,793. Patented Aug. 24, 1886.

I I (No Model.) I' V UNITED STATES PATENT OFFICE,

BEVERLY HALE, OF RUSHVILLE, ILLINOIS.

BALANCED SLIDE-VALVE.

EJPECIIFICATION forming part of Letters Patent No. 347,793, dated August 24, 1886. Application filed October 15, 1985. si nal No. 180,010. (No model.)

which my invention apppertains to make and I use the same, I will now proceed to describe its construction and operation, referring to the accompanying drawings, in which- Figure 1 is alongitudinalsection of asteamvalve and its ease, and Fig. 2 is a cr0ss-section of the same.

A represents the valve-case, which is formed in the usual manner, with inlet-ports a a, and

.exhaustports a a, leading to and from the cylinder through the seat A.

The slide-valve B is of the usual and wellknown form, having cored recesses I) b, for connecting the exhaust-passages, and the seat is formed with a central depression or chamher, I), connected to the steam-supply pipe lit, for obtaining sufficient steam below the valve to balance it.

In all valves of this kind difficulty is often experienced in the proper balancing of the valve by obtaining greater pressure beneath the valve than above it, because the steam from the boiler being admitted direct to the balancing-chamber, and confined there, the pressure is the same as in the boiler, while as the space in the steam-chest above the valve is in direct connection with the cylinder and the valve and piston both move with the steam, the effective pressure on the valve is reduced to the working-pressure on the piston, always less than that in the boiler. As an illustration: If the pressure in the boilerand balancing-chamber is assumed at ninety pounds, the motion of valve and piston will reduce this pressure to about seventy pounds, and the unequal pressure on the upper and under side of the valve lifts it from its seat. this, I provide the valve 13 with a puppetvalve, 0, placed in a small passage, 0, through the main valve, and arranged, as shown, to openupward. This allows the free escape of sufficient steam from one side of the slidevalve to the other to relieve the surplus press ure and retain the valve in its proper position, as will be at once understood.

I do not desire to confine myself to the especial form of relief-valve herein shown and described, but desire to use any form of valve that will accomplish the purpose in view. I

To avoid v thus obtain a more perfect working slidevalve, and relieve much of the strain upon the eccentrics and their rods.

Secured to the valve B is also a small oilcup or receptacle, B, from which a pipe or passage, 0', leads to either end of the valve, and enables me to effectually lubricate the bridges and valve-seat, as will be seen in the drawings.

Having thus fully described my invention, what I claim as new, and desire to secure by Letters Patent, is

The combination, with a steamehest formed with a balancing-chamber connected with the boiler, and a slide-valve working in the chest, of an upwardly-opening puppet-valve placed in a passage connecting the balancing-chamher with the chest above the valve, substantially. as and for the purpose set forth.

In testimony whereof I affix my signature in presence of two witnesses.

BEVERLY I-IA LE.

Witnesses:

JOHN G. BAGBY, Autos H. TRAVIS. 

